What event triggered the start of the Civil War?

some people wanted to not have others come into the country while others didn't so there was a big civil war about it

so the story tells of someone named kaushik choudhuri, but he does not narrate the story, a girl named hema does. hema tells the story in a second person point of view because you (the reader) are supposed to be the boy named kaushik.

here's an excerpt i found: "i was ushered into the fitting room, your mother watching approvingly as i took off my coat and sweater and tried on the bra."

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